CODEWITHSUNDEEP
node.jscsvrethinkdb
Big Skinny
Big Skinny

Reputation: 53

CSV into JSON node js --> rethinkdb

I would like to read a csv file and convert into JSON array of object so I can insert into rethinkdb database. I am working in node js.

A tool called csvtojson convert the csv content into json (see code here below). I tried to put the result into the variable called database. However, the database is still empty in console.log. Do you know why this is the case?

//Converter Class
var Converter = require("csvtojson").Converter;
var converter = new Converter({});

//read from file
require("fs").createReadStream("test.csv").pipe(converter);

var database={};
//end_parsed will be emitted once parsing finished
converter.on("end_parsed", function (jsonArray) {
   console.log(jsonArray); //here is your result jsonarray
   database=jsonArray
});

console.log(JSON.stringify(database))

My output from the test.csv in the console.log is:

[ { Name: 'object 1', Quantity: -100 }, { Name: 'object 2', Quantity: -1750 } ]

My second question:

Is this good enough to insert in the rethinkdb or should I convert into another format for it to work?

Thanks!!

Upvotes: 0

Views: 303

Answers (1)

kureikain
kureikain

Reputation: 2314

It's because JSON.stringify(database) run before event end_parsed fired. In NodeJS, the flow control isn't like in other language, meaning top to bottom, because of JavaScript async. After setting event handler for event end_parsed of converter object. Your program continue to run, without blocking to wait for processing CSV file. At that time, database is still empty.

Simply change it like this:

converter.on("end_parsed", function (jsonArray) {
   console.log(jsonArray); //here is your result jsonarray
   database=jsonArray
   console.log(JSON.stringify(database))
});

will make it works, because database is set and call to console.log inside event handler of end_parsed event.

Is this good enough to insert in the rethinkdb or should I convert into another format for it to work?

Yes, it's. Though a minor point, is probably you should use key like name, quantity to match with many other JavaScript style which is usually camelCase.

Also, you should read here https://rethinkdb.com/docs/importing/ to see if you can just use RethinkDB import to import CSV file directly. I found that CSV import is a bit limited but probably just give it a try.

Upvotes: 1

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